Saji H, Yonekura Y, Tanahashi K, Iida Y, Iwasaki Y, Magata Y, Konishi J, Yokoyama A
Department of Radiopharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
Ann Nucl Med. 1993 Aug;7(3):153-6. doi: 10.1007/BF03164959.
125I-2'-iodospiperone (2'-ISP), which has a high and selective affinity for dopamine D2 receptors, produced a high myocardial accumulation of radioactivity in the early phase after intravenous injection into mice. A human scintigraphic study also showed that the myocardium was clearly visualized soon after intravenous injection of the tracer. Analysis of the myocardial homogenate obtained from mice showed that 125I-2'-ISP was metabolically stable and was taken up the myocardium in its intact form. Administration of spiperone significantly reduced the myocardial uptake of 125I-2'-ISP in mice. Treatment with haloperidol and (+) butaclamol, which have a high affinity for dopamine D2 receptors, also tended to reduce the myocardial uptake of radioactivity, while (-)-butaclamol, which has no affinity for dopamine D2 receptors, caused no change in uptake. These findings suggest that the myocardial accumulation of 2'-ISP occurred in association with dopamine D2 (DA2) receptors.
125I-2'-碘螺哌隆（2'-ISP）对多巴胺D2受体具有高选择性亲和力，静脉注射到小鼠体内后，在早期阶段会在心肌中产生高放射性蓄积。一项人体闪烁扫描研究还表明，静脉注射示踪剂后不久，心肌就清晰可见。对从小鼠获得的心肌匀浆进行分析表明，125I-2'-ISP代谢稳定，并以完整形式被心肌摄取。给予螺哌隆可显著降低小鼠心肌对125I-2'-ISP的摄取。用对多巴胺D2受体具有高亲和力的氟哌啶醇和（+）布他拉莫治疗，也倾向于降低心肌放射性摄取，而对多巴胺D2受体无亲和力的（-）-布他拉莫则不会引起摄取变化。这些发现表明，2'-ISP在心肌中的蓄积与多巴胺D2（DA2）受体有关。
